Objection: Why is the line drawn between vertebrates and invertebrates? True, the nature of spinal cords means vertebrates are generally capable of higher mental processing and therefore have a greater ability to formulate suffering, but you’re counting “ones that lack self-concepts sufficiently strong to have any real preference to exist”. Are you saying the presence of a notochord gives a fish higher moral worth than a crab?
Objection: Why is the line drawn between vertebrates and invertebrates? True, the nature of spinal cords means vertebrates are generally capable of higher mental processing and therefore have a greater ability to formulate suffering, but you’re counting “ones that lack self-concepts sufficiently strong to have any real preference to exist”. Are you saying the presence of a notochord gives a fish higher moral worth than a crab?
That’s a good point—there are almost certainly invertebrate species on the same side of the line. Squid, for example.